Draft gear



Feb. 19, 1929. 1,702,932

w. H. coT'roN DRAFT AGEAR Filed Deo. 1o, 1924 2 sheets-sheer 1 Feb. 19,1929. 1,702,932

w. H. coTToN DRAFT GEAR Filed Dec. 10, 1924 2 Sheets-Sheet 2 Q y lm/fm@Patented Feb. 19, 1929.

UNITEDSTATES PATENT'IOFFICL WALTER H'. COTTON, OE CHIcAGe, ILLINOIS,AssIGNoRv To UNION DRAET GEAR OOM- IANY, OF CHICAGO, ILLINOIS, ACORPORATION OE'DELAWARE.

- :DRAFT GEAR.

Application vfiled December 10, 19,24. `Serial No. 754,912.

This invention relates to draft gears for railway cars, and moreparticularly to draft gears ofthe friction type.`

One of the objects of the invention is improved wedge releasingmechanism.

Another object of the invention is thev provision of a draft gear havingnew and improvedl means for restoring the parts to normal position aftercompression. p

Other objects of the invention arethe provision of a new and improveddraft gear that is easily assembled, cheap to manufacture, efficient inoperation, and that is'not likely to become broken,.distorted orl getout ofl order.

Other and further objects andadvantag'es of the invention will appearfrom thel following description taken in connection with theaccompanying drawings, in which Fig. 1 is a horizotal section of thedevice showing the same in operative position;

Fig. 2 is a section on line 2-2 of Fig. 1;

Fig. 3 is a plan view showing the device in collapsed position, withparts in section and parts broken away;

Fig. 4 is a perspective yview of the follower sleeve;

Fig.r5 is a perspective plate; p

Fig. 6 is a perspective view of the wedge memberl land k Fig. 7 is aperspectivefview of one of the friction plates, on a smaller scale.

On the drawings the reference 10 designates the center sills of arailway car, each of which is provided with a draft lug 11 and bufferlug 12, as is usual in such constructions. The draft gear which ismounted between these lugs comprises the two follower platesll which areadapted to engage the draft and buffer lugs in theusual manner.

view of the spring Mounted `between the followerplates are a' pair ofsleeves 14 within which are mounted the friction elements for resistingthe compression of said sleeves. These friction elements comprise one ormore groups-of plates which are adapted to frictionally engage eachother and the innery sides of the sleeves. Preferably two groups, 15 and16, of intercalated friction plates are employed, one at each side ofthe longitudinal axis of the gear, each groupcomprising the two sets oflplates 17 and 18 overlapping at their inner ends.

Suitable means are provided .for moving they provision of a draft gearhaving new and y the invention, a pair of shoes 19fat each end of thegear Vin contact with the friction plates,

the plates laterally against the sides'of the sleeves in order to createfriction to resist and absorb bufferl stresses during the compression ofvice selected to illustrate one embodiment ofk is provided, which areadapted to be forced laterally by lwedgeblocks20 having the inclinedfaces 21 at each side thereof for engaging vthe corresponding inclinedfaces 22 on said shoes. The Outer ends of the wedge the gear.y In theform of the dei blocks 20 are adapted to extendl beyond the I sleeves1'4 when the gear is in extended position. When the gear is collapsed,the' follower plates 13 will force thewe'dges 2 0 inwardly, therebycausing the 'shoes to move outwardly against the friction plates and onfurther vcollapsing movement the follower plates 13 will engage the endsof the friction plates and the sleeves and collapse the same n againstthe frictional resistance thereof.

kSuitable means are provided for returning the parts to normal positionafter compression. It isdesirable that the meansemployed for thispurpose be so constructed that the wedge blocks will first be releasedand thenthe plates and sleeve will be moved outwardly to normalposition. In the presentA construction the resilient means for releasingthe wedge blocks is also employed to assist in returning the platesandsleeves to inoperative position; As shown on lthe drawing a resilientmember'such as the compression spring 23 is mounted betweensaid wedgeblocks to resist their movement toward each other. The wedge blocks lmaybe provided with recesses 24 for receiving the ends of the springand theparts may be and preferably are heldin assembled lrelation by the rod orbolt 25. The wedge blocks 2() are provided with laterally extendinglugs26 which are adapted to engage retracting bars 27 mounted In notches 28in the frict-ion plates. The `retracting bars .27 are mounted in theoppositely arranged notches 28, see Fig.7, in theouter ends of the twosets of vpla-tes 17 and 18. The inner ends of the plates are reduced asat 29 so thatv they may pass between the retracting bars of the opposedplates during 'their compression. The parts are so arranged that thelugs 26 will not come into engagement with the-retracting' bars 27 untilthe wedgev has'been partially retracted. One of the wedge blocks so,l

Cil

l ward wedge block and caus rlhis is considered an important feature ofthe invention. f

A spring 31 isA employed for yieldingly resisting the inward movement ofthe shoes 19 whereby the same will be Jforced laterally by the wedgeblocks 2O during compression. Suitable means are provided for utilizingl this spring for returning the parts to normal position. As shown, thismeans comprises a spring seat or plate '32 each end of the gearinterposed between the ends of' the spring 81 and shoulders 83 on theshoes 19 for movingthe shoes outwardly after compression. These platesare also provided with lugs or projections 34 which adapted to engagethe retracting bars 2"" each side of the lugs 26 for moving the frictionplates outwardly.

The sleeves or sleeve followers 14 are also moved outwardly aftercompression by the retracting bars 27, A convenient manner ofaccomplishing this is shown on the drawings, which consists in forminglugs on the inner side walls of each 'sleeve adjacent its outer end.These lugs are adapted to be engaged by said bars and moved outwardlysimultaneously with the friction piates.

The coupler butt is provided with a stirrup or loop 36 for embracing thedraft gear, as is usual in such constructions.

The operation of the device is as follows:

Upon the application of stresses of buff, the forwardfollower 13 ismoved inwardly, carrying with it the associated wedge block 2() againstthe resistance ofthe spring 23. The forward shoes 19-19 are wedgedoutwardly and advanced against the opposition of the spring 31, thusforcing the rearward shoes 19-19 backwardly against the rear ng theirlats eral movement. The friction plates are thus put under compressionat bothv ends.

When the forward follower makes contact with the vciuls of the plates 18and the sleeve 14e, all of these elements are carried inwardly, theplates 17 and rearward sleeve 14 also moi/'ing inwardly, due to the highfriction which has been developed, until the .maire contact with therearward follower 13.

The continued advance of the forward follower causes The plates 18 tomove inwardly against the frictional resistance of the parts with which.t-hey make contact, thereby, with the spring resistance, absorbing` thecompressing force. The limit of compressive movement is reached when thetwovsleeves make contact.

Upon release, the forward wedge block 20 and follower 13 are urged totheir nor-A `ward cz sing 14 to normal position. The bars 27 engage thelugs outwardly.

As the spring 31 expands the wedging action fat the inner end of thegear is relieved, but the friction plates remain under sutlicientcompression to insure the restoration of the plates 17 and the innersleeve 1st to normal position.

Und-er the iniiuence of stresses of draft the same action takes place,the movement however being from the rearward end ofthe gear, and uponthe relief vof these stresses the parts are similarly restored to normalpo ion.

It is thought from the foregoing taken in connection with theaccompanying drawings that the construction and yoperation of my devicewill be apparent to those skilled in the art, and Vthat various changesin size, shape proportion and details of construction may be madewithout departing `from the spirit and scope of the appended claims.

I claim as my invention:

1. A draft gear for railway cars comprisinga group of intercalatedplates, a friction shoe at each rend yof said group slidable along oneof said plates, casings enclosing both end portions `of the group ofplates, resilient means for resisting the inward movement of saidshoes,wedge members adapted to engage said shoes for forcing the samelaterally for compressing said plates, resilient means for resisting theinward movement of said members during the 4compression of said gear,and means whereby when the compression of said gear is roleased theresilient means during initial movement will move said members and shoesoutwardly independently and during nal moven'rent will cooperate inmoving said plates outwardly.

2. In a draft gear, a pair of' casings, a group of two sots ofrelativ-ely movable intercalated friction plates within said casings,means for forcing said plates into frictional engagement duringcompression of said gear, plate netracting 'bars for both sets ofplates, a plurality of springs for resistingthe inward movement of saidmeans, and means to move the sleeves whereby said springs will actuatesaid bars successively for. retracting said plates and said casings.

In a draft gear, a pair of casings, a plurality ofsets of relativelymovable inter'- calated friction plates within said casings,

`retracting bars associated with each set of plates, and a meansincluding a plurality of springs for successively actuatingr said barsafter compression of said gear forr returning said plates to normalposition, said bars engaging said casings on release of said gear forreturning the salne to released position.

4l. A draft gear comprising a group of two sets of intercalated. plates,means including friction shoes and a wedge element cooperating therewithat each end of said gear for forcing said plates laterally intofrictional engagement with each other, means to limit the lateralmovements of said plates, resili ent means for resisting the inwardmovement of said wedge elements, retracting bars for each set of plates,and lugs on said wedge elements for engaging said bars during theoutward movement only of said wedge elements, said bars being adapted`to retract said casings during the release of said gear.

5. intercalated plates each comprising two sets of friction'plates, apair'of shoes for engaging said plates at each end of said gear, a wedgemember at each end of said gear for forcing Asaid shoes inwardly andlaterally against said plates, retracting bars connectedV `to andmovable with said plates, resilient means for resisting the inwardmovements of said wedge members, means o n said mem-V bers for engagingsaid bars during the outward movement only of said members, shoulders onsaid shoes, spring seats for engaging said shoulders, resilient meansfor engaging said seats for resisting the inward movements of saidshoes', andmeans on said In a draft gear,- a pair of groups of seats forengagingsaid bars during the final outward movement of said shoes. 6.Ina draft gear, .a pair of casings, a group of intercalated frictionplates within `said casings, means including shoes and wedges vforcreating transverse pressure' on said plates during compression of saidgear, spring-pressed seat members for engaging said shoes, retractingbars interlocking with the plates, resilient means for engaging saidseat members and wedges for causing .the same to act independently onsaid bars for retracting said plates after compression, and means onsaid casings for engaging said bars for retracting said casings uponrelease of the gear. n f f 7. A ydraft gear, comprising members havingfrictional surfaces parallel with the axis of the gear, means includingwedges for forcing said surfaces into frictional engagement duringcompression of said gear,

kspring means for engaging said wedges,

retracting elements, means on said members adapted to be engaged by saidelements for retracting the same upon the release of the gear, andspring-pressed means for resisting the inward movement of the shoesduring compression of the gear land adapted to engage said shoes andsaid retracting'elef ments on the release ofthe gear.

i 8. A draft gear comprising members having frictional surfaces, -meansincluding wedges and Vcooperating shoes for forcing said surfaces intofrictional engagement,

resilient means for resisting the inward movement of said shoes andwedges, retracting bars positively engaging shoulders on the first-namedmembers,and means associated with said shoes and wedges for successivelyengaging said bars for vreturning the parts to normal position aftercompression.

In testimony whereof` I affix my signature.

- WALTER COTTON.

